#include <stdio.h>
#define FIRST 10
#define SECOND 15

int GetSum(int, int); 

main() {
	int x, y, z;
	x = FIRST;
	y = SECOND;
	z = GetSum(y, x);
	
	printf("%d", z);
	getch();
}

int GetSum(int a, int b)
{
	int rezult; 
	int BmA; 
	int temp; 
	rezult = 0;
	
	BmA = b - a;
	

	while (BmA > 0) {
		temp = BmA;
		rezult = temp + (--BmA);
	}
	
	return rezult;
}
     
